Merge pull request #80 from mlabs-haskell/dev/notes-on-submitter

Document the subtleties of the $SUBMITTER_PKH

Author: bladyjoker

README.md

@@ -300,12 +300,15 @@ declare -x GOD_PKH="c12aacc2604e89cd5dac1fb1e324ad552df1b18e2bd4230e8e15cfd5"
 declare -x SUBMITTER_PKH="b7e59f40866e6ec88635343b9cc285043d344afbbe001ae645db0553"
 ```
 
-Output shows some named wallets with their base16 public keys hash identifier. The `SUBMITTER_PKH` is the only wallet not used by the `COOP Publisher` that belongs to the user. In fact, we need to hide this wallet from the `local-cluster` to emulate a real scenario:
+Output shows some named wallets with their base16 public keys hash identifier. The `SUBMITTER_PKH` is the only wallet not used by the `COOP Publisher` that belongs to the user. We want to hide this wallet from the `local-cluster` to emulate a real-world (distributed) scenario where a third-party user will eventually sign the resulting COOP transaction:
 
 ```sh
 mv $WALLETS/signing-key-"$SUBMITTER_PKH".skey $WALLETS/my-signing-key-"$SUBMITTER_PKH".skey
 ```
 
+> NOTE:
+> If the `$SUBMITTER_PKH` signing key is not renamed, when the [Publisher gRPC](coop-proto/publisher-service.proto) service is invoked (below) it will use the key to automatically sign a COOP transaction and submit it to the Cardano Network. This can be useful in test-scenarios or when using COOP in an appropriately secured environment, purely as a publishing mechanism, i.e. in a centralized or federated model the COOP node signs and submits its own transactions. In this scenario the `FEE_PKH` can also be set to that of the `SUBMITTED_PKH` so that fees are automatically returned.
+
 All other essential wallets are owned by the COOP Publisher and are used throughout its lifecycle. We'll revisit their role as we progress through the tutorial.
 
 The `make-exports` and `show-env` are provided Bash functions that wrap the parsing of `local-cluster` information and set the appropriate environment variables.